Sir Richard Branson tonight offered the first public glimpse of the aircraft he hopes will become the first commercial vehicle to send passengers into space.

The head of the Virgin business empire stood proudly by his latest creation, called SpaceShipTwo, showing it off to a crowd of investors, politicians, would-be passengers and journalists ahead of a lavish theatrical rollout planned for late tonight in the wilds of the Mojave Desert in southern California.

The six-passenger craft, a dramatic-looking space-age creature with a sleek fuselage and radically upturned gull wings, could be sending paying customers into orbit just above the earth's atmosphere as early as 2011 – a two-and-a-half-hour experience costing $200,000 (£122,000) a pop.

Branson said: "For most of us, escaping the constraint of gravity is something we have only been able to achieve in our dreams – until now."

SpaceShipTwo would be carried into the skies by its mothership, a carrier aircraft resembling a large catamaran named WhiteKnightTwo, which was unveiled to the public last year.

Once aloft, the spacecraft would be untethered and allowed to shoot up at supersonic speeds to about 62 miles above Earth's surface – beyond the noise and heat of the atmosphere and into the suborbital sphere of weightlessness and utter calm.

After just a few minutes in space, the craft would then re-enter the atmosphere using a revolutionary technology that allows the craft to find the right angle without the intervention of either the pilots or computers.

Branson said he wanted to "bring space travel down to a price range where hundreds of thousands of people would be able to experience space, and they never dreamed that could happen in the past".

The crucial so-called "care-free" re-entry technology is the brainchild of America's leading space technologist, Burt Rutan, who first demonstrated it with his own prototype craft, SpaceShipOne, and won the prestigious Ansari X prize in 2004. Virgin and Branson partnered up with him shortly afterwards.

SpaceShipTwo is twice the length of SpaceShipOne – about 60ft (18 metres) long, compared with the old craft's 28ft – and is designed to carry non-astronauts. Passengers would train for three days before the flight and wear space suits enabling them to float about the cabin during the weightless part of the journey.

Around 250 people – everyone from Victoria Principal, the actress who starred in Dallas in the 1980s, to Bryan Singer, the film director, to the physicist Stephen Hawking – are reported either to have paid the fee in advance or put down a deposit.

Last night's ceremony at the Mojave air and space port promised to be an extravaganza marrying scientific knowhow with old-fashioned Hollywood glitz – despite forecasts of freak rainstorms and cold temperatures. Arnold Schwarzenegger, California's governor, was expected to headline the event, taking place at a custom-built arena featuring two huge domes, tents and other structures along with batteries of bright lights.

Some of the paid-up future passengers on SpaceCraftTwo were allowed a sneak peek of the craft and its mothership over the weekend. Television crews followed in the early hours of this morning, offering viewers their first glimpse.

Branson himself relished his role: part entrepreneur, part marketing guru and part showman. "This will be a trip like no other," he promised.

The journey from space dream to commercial reality has not been problem free. An accident in which three engineers were killed in a nitrous oxide explosion in 2007 set back the development timetable. And a packed programme of flight tests and other experiments still lies ahead before the maiden voyage into space – a voyage that Branson and his children will probably be the first to undertake.

The pieces are, however, slowly falling into place. In June, Virgin Galactic – as the dedicated company is called – broke ground on a "spaceport" in southern New Mexico, using a design developed in part by Sir Norman Foster's architectural firm.

And in July, a group of investors, Aabar Investments of Abu Dhabi, came on board with $280m, taking a 32% stake in Branson's company.